Study of influence of vertical velocity and density profiles on hydrodynamic stability of zonal flow
Abstract
Within the framework of the linear theory of hydrodynamic stability and on the basis of a three-layer model of a zonal current with transverse velocity shear a study was made of the joint influence of curvature of the vertical velocity and density profiles on the parameters of unstable wave disturbances and the findings were compared with theoretical studies made earlier and data from in situ observations. The problem is formulated as follows: there is a three-layer macroscale current (with small Rossby-Kibel' numbers Ro 1) on the Beta-plane not bounded along the longitudinal coordinate X, directed to the east, and having the width L along the transverse coordinate Y, directed to the north, with the Z axis being directed vertically upward. In this formulation a system of equations is derived which is free of shortcomings present in earlier attempts to solve this problem. This makes it possible to study the influence of the vertical curvature of the density profile, related to the simultaneous existence of a seasonal thermocline and constant pycnocline, as well as the influence of curvature of the vertical velocity profile arising in the presence of subsurface velocity maxima. The system of equations is solved numerically.
- Publication:
-
USSR Report Earth Sciences JPRS UES
- Pub Date:
- June 1985
- Bibcode:
- 1985RpESc.......41B
- Keywords:
-
- Hydrodynamics;
- Ocean Currents;
- Ocean Surface;
- Velocity Measurement;
- Water Waves;
- Zonal Flow (Meteorology);
- Curvature;
- Density Distribution;
- Linearity;
- Thermoclines